REGIONALIZATION OF BIOSOLIDS PROCESSING: GOOD FOR BIOSOLIDS; HARD ON LIQUID PROCESSING

With the high costs associated with some of the advanced biosolids treatment processes, regionalization is one means of taking advantage of the economy of scale of these systems. In addition to helping reduce overall capital expenditures, operations and maintenance costs can be reduced through economies in staffing. However, there is a tradeoff to these economic advantages – sidestream treatment. This paper discusses benefits and disadvantages of regionalization of biosolids processing and the relative impact of sidestream return loads on the liquid treatment processes. One example presented in this paper is based on work performed for a new regional management authority considering the development of a regional biosolids processing facility. Another study evaluated how an existing regional facility will be affected when its liquid treatment processes upgrade to full biological nutrient removal. Several sidestream treatment approaches for nitrogen and phosphorus removal are also discussed.